[time-nuts] Re: World's most accurate PC clock!

Bill Hawkins bill at iaxs.net
Sun Jul 3 14:56:44 EDT 2005

Tom Van Baak wrote:

"There are more worries besides stability. Many OS's
have a problem, under conditions of heavy load, of
missing a clock interrupt every now and then. When
this occurs it spoils the benefit of having a ultra-high
accuracy xtal."


A 300 MHz Pentium running Windows 98 SE ran +/- 5 seconds
per day if it was just doing Word processing. If a directory
of 20,000 files was searched or backed up then it would start
losing time, to minutes per day. A reboot was required to get
time back on track. IIRC, it would boot back to the correct
time. Now I use SNTP and an Internet server with Mount Hay's
Timeserver v1.23 or Tardis in W2K and XP machines.

Modern PCs have a millisecond interrupt for processing sound
files, forgot what it's called. Maybe you could get an accurate
clock if the PC wasn't doing anything else and definitely not
connected to the Internet for cookie polling.

TrueTime used to make PC boards that would slave to an external
standard. Don't know if they ran internal time counters and had
their own time display software.

Bill Hawkins

It's not precision time, it's just adequate time.
64 KB is enough for anybody.

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